atrac9dec: relax gradient value requirements

Unlike the range, the gradient start value does not have to be lower
than the end value.
Does allow more files to be correctly decoded without errors.

Signed-off-by: Rostislav Pehlivanov <atomnuker@gmail.com>

diff --git a/libavcodec/atrac9dec.c b/libavcodec/atrac9dec.c
index 629757f63d76f30bc69c5f7f76c92c7514a0954d..28f8fef174d6f681b795d9383d952c301ad6cf43 100644 (file)
--- a/libavcodec/atrac9dec.c
+++ b/libavcodec/atrac9dec.c
@@ -123,7 +123,7 @@ static inline int parse_gradient(ATRAC9Context *s, ATRAC9BlockData *b,
     if (grad_range[0] >= grad_range[1] || grad_range[1] > 47)
         return AVERROR_INVALIDDATA;
 
-    if (grad_value[0] >= grad_value[1] || grad_value[1] >= 32)
+    if (grad_value[0] > 31 || grad_value[1] > 31)
         return AVERROR_INVALIDDATA;
 
     if (b->grad_boundary > b->q_unit_cnt)